Microstructure of Superconducting Cable Components

Abstract

Using atomic force, optical and electron microscopy methods, the changes in the microstructure and phase composition were investigated for the alloy Nb47%Ti used for the manufacture of superconducting cable employed as current-carrying elements in the magnetic system for International Thermonuclear Experimental Reactor. The test samples were prepared from the superconducting wire at an intermediate step of the drawing process for the area reduction Ø1.3→Ø1.2 mm. The effect of cold drawing and intermediate annealing on the properties of as-worked Nb-Ti alloy was assessed. Local strain zones were found to occur in the rupture area. The shape and chemical composition of Nb-Ti wire was examined for both a defect-free area and the rupture area. A Nb diffusion barrier was found to occur in the copper matrix of NbTi wire.

Effect of Radial Forging on the Microstructure and Mechanical Properties of Ti-Based Alloys

“…According to research conducted over recent decades [3][4][5][6], the possibilities of improving the above properties by means of the conventional mechanical and thermal processing methods in order to modify the chemical composition of titanium-based alloys, aimed at introducing alloying elements and varying grain size in the parent material, are almost exhausted. On the other hand, it is evident that strength characteristics along with functional properties of alloys can be noticeably increased via the formation of micro-and submicrocrystalline phases in the bulk of the alloy under severe plastic deformation [7][8][9].…”